This invention relates to the sizing of textile fibers for use in weaving with water jet looms and, more particularly, to the use of ammonium salts of certain carboxylic acid copolymers as warp sizes for such textile fibers.
A warp size is a chemical applied to a yarn comprising a warp for the purposes of protecting the yarn during subsequent handling and weaving. In these operations the yarns running in the warp direction are subjected to considerable abrasion from guide surfaces of split rods, drop wires, heddles, reed, shuttle and adjacent yarns. On a staple fiber yarn such as cotton, the size coats the yarn, protects it against abrasion and covers up such warp defects as knots, crossed ends, slubs and weak spots which occur in the normal variation of textile production. This is accomplished because the size glues down the protruding fibers, and provides an abrasion resistant coating for the fibers. On a filament yarn, the size coats the yarn and cements the filaments together to form essentially a monofilament yarn, thereby preventing chafing between filaments and between the yarn and guide surfaces.
Sizes such as corn starch, gelatin, carboxy methyl celluloses, polyvinyl alcohol, polyacrylic acid and styrene/maleic anhydride copolymers and alkali metal salts of ethylene/acrylic acid copolymers are conventionally employed as warp sizes for weaving on conventional fly shuttle looms as well as the more modern shuttleless rapier and projectile looms. However, due to the sensitivity of the conventional sizes to moisture, the weaver must carefully control weave room humidity to optimum levels for the size being used. This water sensitivity of conventional sizes renders such sizes totally unacceptable as sizes for warps to be woven on modern water jet looms.
In a water jet loom, a high pressure jet of water is used to carry the weft yarn through the loom shed, thereby forming the pick. During this operation, the warp yarn becomes saturated with water. If the warp yarn has been sized with conventional, water sensitive sizings, the size soon becomes water swollen and gummy causing yarn-to-yarn entanglement and size buildup at the heddle eyes and reed. Under such conditions, spun warp yarns break and filament yarns entangle, either of which necessitate stopping the loom. In view of the difficulties resulting from the use of conventional sizes on the water jet loom, weavers wishing to utilize the water jet loom must either use a relatively high twist unsized filament yarn or a low twist filament yarn sized with a water-insensitive composition. Use of a high twist yarn is feasible only in the manufacture of a few types of cloth, thus limiting the versatility of the water jet loom. Unfortunately, the water -insensitive sizes now being employed in the manufacture of fabrics employing low twist filament yarns are not totally water-insensitive and do not adhere well to the yarn.
In view of these difficulties existing in the weaving of textile fibers by water jet looms, it would be highly desirable to provide an improved process for sizing textile fibers for use in weaving with water jet looms and subsequently to desize the woven material.